BRZ Steering Right Tightening + VSC Fault??

[BRZ2Bars]

Hey,

I'm after a little help here, so after I had the car in for its second service, including an alignment, rear diff oil change and brake fluid change, I'm now getting this out of place tightening when turning right above about 65kph. Like there's a non linear steering set up or something, but only turning right. I liken the feel to a car that follows ruts in the road but even when its flat, and I stress it only does it turning right.

Its occurring with the wheel only about 30 to 50 degrees rotation. At the climax of this tighten (so to speak) it then sets off the VSC with random corrective brake inputs despite the car being in control. Pretty unnerving. OBD read from Subaru tells me the car is trying to rectify an under-steer situation despite no such thing occurring.

Points to note are that the first alignment was terrible. Steering wheel 10degs left to go straight sort of thing, and the car didn't track properly. So initially I thought it was that and sent it back to be corrected. They didn't give me a specs sheet however assured me that all measurements were within Subaru specified limits, as it was the first time albeit with the wheel off center...

Following this car felt much better, yet still doing this funny tighten turn in thing.

Since then my Subaru mechanics have attempted all manor of things, wheel rotations to every combination. An inspection of all suspension parts and components numerous data logs and that, including at the time of this issue occurring, and they still are unable to rectify it. The data went to Subaru Tech Australia, and then on to Japan, as they had not heard of anything like this.

The guidance received back down led to them checking and replacing the rh rear hub assembly (wheel speed sensor issue was the thinking) rear left shock (after a leak was found). This improved it slightly but its still occurring.

Other things I'm taking to Subaru to investigate are whether a VSC re centering is required, I've read after big toe adjustments this can throw it out, or steering angle sensor.

I personally feel as though its something mechanical, bent perhaps? Why would it turn in at a non linear rate for only that specific amount of wheel movement, and it does this regardless of VSC setting, but then something also upsetting the VSC computer both in normal and sport modes.

Anyone have any more ideas?

Oh PS its a MY13 BRZ Manual. 18K KM on the clock. No mods, or accident damage under my ownership (from 10k KM) and no visible accident repairs.

Cheers

Nick

[BRZ2Bars]

No ideas anyone?

Dealer seems to think its the Tyres, i'm not totally convinced

[FirestormFRS]

I'm not 100% sure how the steering column links to the rack in these cars.

But I had the same issue with my truck and it would feel like it was binding when you turned to the left. The U joint in the steering linkage to the rack was bad. Replaced the linkage and the problem went away. Not sure again if it's relevant, thought I'd share though.

[BRZ2Bars]

Here's a video which poorly (sorry for the quality) illustrates what i'm talking about above. [ame="https://www.youtube.com/watch?v=5t81ihjBKk0"]YouTube[/ame]

[Augora]

Video indicates it's "private" so can't be viewed.

Shop manual for the car indicates that the last step of the "wheel alignment" procedure is a VSC midpoint setting reset. Steps listed --

1. VDC sensor midpoint setting mode

CAUTION:

·When the skid control computer (brake actuator ASSY) has been replaced, make sure to perform VDC sensor midpoint setting.
·Make sure to perform [VDC sensor midpoint setting mode] on a level surface (grade of 1 % or less). While centering, do not shake the vehicle or open/close a door

Note: When performing [VDC sensor midpoint setting mode], make sure to set zero point of yaw rate sensor & G sensor (brake actuator ASSY is integrated) and steering sensor.

(1) Turn the ignition switch to OFF.


(2) Shift into neutral and apply the parking brake.


(3) Connect the SSM3 to the DLC3.


(4) Turn the ignition switch to ON.


(5) Set the steering wheel in a straight position.


(6) On the SSM3 screen, select [ABS/VDC System]→[Work Support]→[VDC sensor midpoint setting mode].


(7) Following the SSM3 screen, perform [VDC sensor midpoint setting mode].